The Greater Horn of Africa is facing a looming polycrisis fueled by a multitude of factors, including conflict, prices, climate, and disease. This region, already beset by prolonged crisis and conflict, is now at risk of a major, multicountry crisis due to the combination of El Niño, the war in Iran, and internal conflicts. The impacts of these factors are likely to be catastrophic, affecting both crops production and grazing, as well as the livelihoods of rural populations. The region is also facing an unpredictable variant of the Ebola virus, which could spread to South Sudan and exacerbate the crisis. The ongoing conflicts in the region, particularly in Ethiopia, South Sudan, and Somalia, are making it difficult to address the impact of climate, health, and price shocks, and risk further exacerbating or accelerating individual drivers. The war in Iran has led to significant increases in transportation and food costs, as well as a fertilizer shortage, which could reduce harvests and keep food prices high long after the active conflict ends. The Horn of Africa will be doubly affected by the fertilizer bottleneck, as local production will be reduced and global food prices will be higher. The combination of climatic, conflict, market, and epidemic shocks is not simply additive but multiplicative, with each intensifying the other. Climate and epidemic shocks almost inevitably exacerbate conflict and encourage crackdowns on population movements. The deliberate gutting of the global humanitarian response infrastructure has undermined the international system's capacity to respond to major shocks, and the region is less prepared to cope with the looming crisis than during previous El Niño years. The onus will be more heavily on governments, civil society, and local communities in the Horn to mitigate anticipated shocks and their fallout. Local mutual aid efforts have ramped up significantly and effectively, but they can be better supported with complementary funding. The most worrisome driver behind this polycrisis is violent conflict, which complicates any response to crisis and raises the risk of starvation being used as a weapon of war. The international community has been unwilling to hold warring parties and their foreign supporters accountable for intentionally starving parts of their populations. Data and monitoring systems have also been significantly crippled by aid cuts and misinformation, making it difficult to understand the gravity of these crises or to keep actors accountable. The conjunction of so many potential hazards has all the hallmarks of the proverbial perfect storm. Without immediate prevention measures, the looming polycrisis will have widespread impacts on basic health, nutrition, and water services, and the potential for mass mortality and displacement.